06.从尾到头打印链表
一、 题目
输入一个链表的头节点,从尾到头反过来返回每个节点的值(用数组返回)。
示例 1:
输入:head = [1,3,2]
输出:[2,3,1]
二、 解法
2.1 辅助空间
func reversePrint(_ head: ListNode?) -> [Int] {
var res: [Int] = [], node = head
while let n = node {
res.insert(n.val, at: 0)
node = node?.next
}
return res
}
2.2 递归
func reversePrint(_ head: ListNode?) -> [Int] {
guard let node = head else {
return []
}
return reversePrint(head?.next) + [node.val]
}
Last updated
Was this helpful?